BACKGROUND Antimicrobial therapy with appropriate biliary drainage is considered the standard of care for acute cholangitis, but the optimal duration of antimicrobial therapy remains unknown. Seven to 10 days of antimicrobial therapy are common for the treatment of acute cholangitis, but a recent retrospective cohort study suggested a shorter duration might be effective. A shorter duration of antimicrobial therapy can be beneficial in decreasing the length of hospital stay, improving patients' quality of life, decreasing adverse effects, and even contributing to a decrease in the occurrence of antimicrobial resistance. METHODS/DESIGN We will conduct a multi-centre, open-label, randomized, non-inferiority trial to compare short-course therapy (SCT) with conventional long-course therapy (LCT) in treating patients with acute cholangitis. SCT consists of 5-day intravenous antimicrobial therapy if the patients had clinical improvement, while at least 7 days of intravenous antibiotics will be provided to the LCT group. The primary outcome is clinical cure at 30 days after onset. Patients will be randomly assigned in an open-label fashion. A total sample size of 150 was estimated to provide a power of 80% with a one-sided α level of 2.5% and a non-inferiority margin of 10%. DISCUSSION This trial is expected to reveal whether SCT is non-inferior to conventional LCT or not, and may provide evidence that one can shorten the treatment duration for acute cholangitis for the benefit of patients. TRIAL REGISTRATION University Hospital Medical Information Network, UMIN000028382. Registered on 30 August 2017.

中文翻译：

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缩短急性胆管炎治疗的抗生素持续时间：一项开放标签的随机对照试验的理论基础和研究方案。

背景技术具有适当的胆汁引流的抗微生物治疗被认为是急性胆管炎的标准治疗方法，但是抗微生物治疗的最佳持续时间仍然未知。急性胆管炎的治疗通常需要7到10天的抗菌治疗，但是最近的一项回顾性队列研究表明，持续时间较短可能有效。较短的抗微生物治疗时间可有益于缩短住院时间，改善患者的生活质量，减少不良反应，甚至有助于减少抗药性的发生。方法/设计我们将进行一项多中心，开放标签，随机，非劣效性试验，以比较短程疗法（SCT）与常规长程疗法（LCT）在治疗急性胆管炎患者中的作用。如果患者的临床状况有所改善，SCT包括5天的静脉抗菌治疗，而LCT组将至少提供7天的静脉抗生素。主要结果是发病后30天的临床治愈。患者将以开放标签的方式随机分配。估计总样本量为150，可提供80％的功效，单面α值为2.5％，非劣质性余量为10％。讨论预期该试验将揭示SCT是否不逊于传统LCT，并可能提供证据表明可以缩短急性胆管炎的治疗持续时间，使患者受益。试验注册大学医院医学信息网，UMIN000028382。2017年8月30日注册。